Answer:
a) v = 88.54 m/s
b) vf = 26.4 m/s
Explanation:
Given that;
m = 1400.0 kg
a)
by using the energy conservation
loss in potential energy is equal to gain in kinetic energy
mg × ( 3200-2800) = 1/2 ×m×v²
so
1400 × 9.8 × 400 = 0.5 × 1400 × v²
5488000 = 700v²
v² = 5488000 / 700
v² = 7840
v = √7840
v = 88.54 m/s
b)
Work done by all forces is equal to change in KE
W_gravity + W_non - conservative = 1/2×m×(vf² - vi²)
we substitute
1400 × 9.8 × ( 3200-2800) - (5 × 10⁶) = 1/2 × 1400 × (vf² -0 )
488000 = 700 vf²
vf² = 488000 / 700
vf² = 697.1428
vf = √697.1428
vf = 26.4 m/s
Answer:
The first flowering plants appeared in the Mesozoic era, not the Paleozoic era
Explanation:
The Mesozoic era is well known and most famous because of the rule of the dinosaurs which were the dominant animals for most of this are. Also, it is the era in which the mammals appeared, though they lived in the shadows of the dinosaurs and only became dominant after their extinction. Another important evolution that took place and is not mentioned very often is the appearance of the first flowering plants. This was a revolutionary trait for the plants, and it helped them to survive in the changing climate on Earth. Soon this trait enabled this type of plants to spread out significantly and to become one of the most dominant organisms on the planet in the following era.
The first one is electrical energy
Step 2: Use the slope to find<span> the y-intercept. </span>Line<span> is </span>parallel<span> so use m = 2/5. </span>6<span>. </span>Find<span>the </span>equation<span> of a </span>line passing through the point<span> (8, –</span>9<span>) perpendicular to the </span>line<span> 3x + 8y = 4.</span>
Answer:
Fd
Explanation:
Work is force times distance. If you push on an object really hard but it does not budge, you have still performed no work on it, because anything times zero is still zero.